Process of preparing beta-sulfoalkylesters of carboxylic acids



Nov. 18, 1958 H. H. TIEDEMANN 2,861,090

PROCESS OF PREPARING fl-SULFOALKYLESTERS OF CARBOXYLIC ACIDS Filed Oct. 5. 1954 Hermon H. T iedemonn INVENTOR BY I I ATTORNEYS PROCESS OF PREPARING fi-SULFOALKYLETERS 1 OF CARBOXYLIC ACIDS Herman Tiedemann, Fanwootl, N. J., assignor to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware Application October 5, 1954, Serial No. 460,438

6 Claims. (Cl. 260-400) This invention relates to an improved process of preparing esters of carboxylic acid chlorides and Z-hydroxy alkane sulfonic acid salts of alkali metals, alkaline earth metals, periodic table group 23 metals, and organic bases. I

The reaction of fatty acids, fatty acid chlorides and fatty acid esters with 2-aminoor 2-hydroxy-alkane sulfonic acids and the alkali metal salts thereof to yield anionic surface active materials useful as wetting, cleansing, softening and dispersing agents is well known. In U. S. P. 1,932,180 several processes are described for the preparation of such surface active materials. The processes fall into three categories wherein (1) a free fatty acid dissolved in an aliphatic amine is mixed with anamino-alkane sulfonic acid (taurine) and then heated to boiling, (2) an alkyl ester of a fatty acid is heated with the sodium salt of. an amino-alkane sulfonic acid and (3) a carboxylic acid chloride is treated in aqueous medium with a 2-amino-alkane sulfonic acid in the presence of caustic soda. The latter process is the conventional batch method of manufacture and involves charging the solid alkali metal salt of 2-hydroxy alkane sulfonic acid and the carboxylic acid chloride to a kettle equipped with a highly powered agitator and breaker arms or to a sigma bladed kneading machine, i. e. a Werner-Pfleideren' After completion of the reaction at approximately 140 C. the reaction mass is cooled and grounded in the reactor. The major portion of the hydrochloric acid by-product is evolved over a very short period, near the peak reaction temperature. Recovery of the by-product requires a large expensive recovery system due to the high intermittent loading.

The conventional batch method not only involves high capital requirements, high. operating expenses, and low product activity, but, in addition yields a product which is dark in color with a disagreeable odor. This darkening is highly undesirable since for commercial applications the product should be as nearly colorless and substantially odorless as possible.

To provide a process which was overcome the foregoing disadvantages, constitutes the principal object of the present invention.

ture and yields a solid B-sulfoalkylester of the fatty acid usefulas a surface active agent. By this process, when compared with the conventional batch process, the following advantages are obtained:

(1) Lower capital requirements (2) Lower operating expenses r, 2,861,090 Patented Nov. 18, 195 8 ICC q as (3) Higher product activity (4) Improved odor (5) Improved color (6) Continuous uniform evolution of by-product hydrochloric acid instead of intermittent high rate evolution In practicing the present invention, the alkali metal, alkaline earth metal, periodic table groupZB metal, or an organic base salt of a 2-hydroxy alkane sulfonic acid is ground in a conventional attrition mill to reduce the average particle size between 3 and 7 microns. The ground solid salt is mixed with the fatty acid chloride to form a homogeneous non-settling slurry. This mixing is preferably accomplishd in any suitable, separate container lined with glass or a sturctural material which is resistant to fatty acid chlorides. The container is equipped with a discharge line of suflicient diameter to permit the flow of the mixture of the slurry by gravity or the discharge line provided with a proportioning pump, so that the slurry may be fed continuously into the reaction chamber. The reaction chamber consists of the conventional hot rolls, a heated continuous belt,'or a double drum drier, which is heated with pounds of steam per square inch. The rolls or continuous belt may be heated in any conventional manner, such as, for example, infra-redlamps, electrically heated elements, steam coilspositioned between the rolls or belt, etc. The temperature may range from 170 C. As regards the double drum drier, the temperature corresponding to 90 pounds steam is approximately 166 C. The slurry is fed continuously into the heated rolls, belt or double drum drier and is deposited asathin film on the surface of the rolls, belt or rotating hot surface of the drum drier to form a hard, semi-brittle film. The contact time required to form the film may range from 4 to 40 secends, depending, of course, upon the temperature of the rolls, belt, or drum drier. The higher the temperature, the shorter is the contact time. As soon as the film is formed, it is lifted from the rolls, belt or drum drier by conventional doctor blades and deposited into a separate container made out of glass or non-corrosive matetemperature, the film becomes hard and brittle, readily breakable and friable on grinding. The hydrochloric acid by-product is evolved continuously at a steady rate from the rolls, belt or double drum drier, and can be recovered in any conventional absorption system. The hard brittle broken film is then ground in the conventional manner.,

The foregoing objects and disadvantages will appear more fully, by reference to the drawing in which there is illustrated a flow sheet for the continuous manufacture of the fi-sulfoalkylesters of fatty acids.

Referring to the drawing, the solid saltof 2-hyd1'oxy alkane sulfonic acid is ground in a conventional" attrition mill for a sufiicient period of time to reduce the average particle size to at least 10 microns and preferably between 3 and 7 microns. The ground solid is then intermittently or continuously mixed in vessel 1 equipped with a water cooling jacket 3 with the carboxylic acid chloride to form a homogeneous non-settling slurry The.

. opening 8. The rolls 7 of the drum drier rotate at a speed to form one complete cycle of 660 seconds dur ing which the film formed is lifted from the rolls 7 by means of doctor blades 9 and deposited into a separate container 10 provided with a suitable conveying means 11 from which the final product is discharged into receivers 12. Hydrochloric acid as a by-product passes through the recovery system 13. The size of Vessel 1 may vary and the feed stoclt can be prepared batch-wise or continuously. For practical ep rposes a 5 gallon stainless steel drum standing in a were; trough tor cooling and equipped with suitable mixing may be employed is: .somme eiel m nufa ture Th p op t g ,pump 4 i con tru ted of stainles s eel'and has a capacity up to 9 gallons per hour. The feed line or -fced line pump 5 is also-constructed of stainless steel. The-conventional double drum drier 6 is usually a square toot Bu-fiovak drier-equipped with chromium plated rolls 7 andis operated at 110 revolutions per minute. Larger units of this type of apparatus may be employed for the pnr-pose of the presentinvention. In such casetheyare equipped with stainless steel rolls. Here, too,-the=fi-nal product is removed by doctor blades 9 and carried out of the-unit-with Water cooled stainless steel conveyor 10. The receivers 12 consist of stainlesssteeldrums or hoppers 'or fiber drums. The hydrochloric absorption system 13 is the conventional one and capable of producing 20 B. muriatic acid.

As an alternative, instead of employing the reaction vessel 1 with agitating means 3, a large cylindrical tube withan outlet and inlet containing within its interior a screw-type mixer may also be efficiently employed.

In forming the slurry of the reactive components, the

molar ratio of the salt of the -2-hydroxy alkane sulfonic acid to carboxylic acid chloride may be varied from 0.95:1 to 1.6:1.

. The Zahydroxy alkane sulfonic acids, which are converted into alkali metal, alkaline earth metal, periodic table group 2B metal or organic base salts, and employed in accordance with the foregoing process are characterized by the following general formulae.

whe ein it re resen s e e hyd ogen, lower alkyl. et l ethyl vprepyl, uty etc., M epres ts a a k i me e.- gy t um. s dium a d po as um; al al n ea m L.

e. g. calcium, strontium, barium, periodic table group 2B meta ea m nesiu ete, or an o gani bas e- Cp risiih qu n line, riet anelat i e e c, nd m epr se ts l or It is to be note t a a y or a i b Whethe aliphati or alieyel e, sat rated o n atur e ma be emp o e in ead f e a orementioned spe ifi bases As exam les o .Z-hvdrexy ellsane sul ni c ds h es rified with earbex i' id chl ride h followng are l u t ti e;

Isethionie a i fi-Hydroxy-dimethylether-fi-sodiu sulfonate firHYdI'OXY-dlfithYlfithfiI-fi-SOdlllm sulfonate 2.-hydroxys2.-methylethane sulfonic acid 1,2-dimethyl-2-hydroxy sulfonic acid 2shydroxy-2-ethyl-sulfonic acid Z-hydroXyq:ropane-sulfonic acid .2rhydroxy-Z-butane-sulfonic acid EZ-hydroxy-lsbutane-sulfonic acid has a minimum of 6 carbon atoms. Acids of this type may be caproic acid, capryllic acid, capric acid, lauric aeid, myristic acid, palmitic acid, stearlc acid, oleic' acid,

linoleic acid, tall oil acids, naphthenic acids, abietic acids,

etc., alkyl benzoic acids such as, dodecylbenzoic acid, .uonylbenzoic acid, octylbenzoic acid, acids from 0X0 alcohols and aldehydes, acids from oxidized petroleum fractions, etc., alkylated phenyl acetic acids, e. g. pdecylphenyl acetic acid, m.-nonylphenyl acetic acid, etc., acid mixtures from various natural plant and animal oils such as olive, tallow, castor, peanut, coconut, soybean, cottonseed, ucahuba, linseed; fish oils such as cod, herring, menhaden, etc., neats foot, sperm, palm, corn, butter, babassu, kapok, hempseed, mustard, rubber-seed, rape, safflower, sesame, etc., may also be employed.

The salts of the 2-hy.droxyalkane .sulfonic acids are readily prepared by neutralization of the acids with an equivalent amount of alkali metal, alkaline earth metal, or a periodic table group 23 metal hydroxide or carbonate, or an organic base in'the conventional manner.

The esterification reaction is carried out at approximately l20-170 C. The heat necessary to reach these temperatures is provided by the aforementioned elements. At he speci ie tempera ure r nges, pret rab y arou 149 he r act on m ssis a pu y-l ke material and is deposited a a thin ilm on he r at ng hot rolls into a ha d. em -britt ei m by the me i pas es t eugh a 240 arc of rotating, requiring 4 to .40 seconds contact time. Ihe 11m affterleavinathe dr m i l f ed bythe on en; n doctor b ad and ee ling to roo emp rature, betnes a hard. brittl broken film hich s t iable on grinding.

The ollowing xamples iiliurth r l s ate the n ture or he impre ed process whieh, ho e i o o be considered liniitati ereo The. Pa given are all by weight.

Example I Example II A non-settling homogeneous slurry consisting of parts of oleic fatty acid hl ride 0% P y) a d 72 parts of ground Sodium isethionate (98% purity) having a particle size of 4 microns was fed to a Z-square foot double drum drier. parts of a hard, brittle product having a B-sulfoethylester content of 83% were obtained.

Example 111 Examp I Was epe ed wi h the except on t 41,. pa ts of h e nu i y a id eh d lan 2.6 pa ts o d so et i nat e e r pla e by 1 pa o ou ydr y Pr p ne di m Su ta a e h ing a p c e iz of 5 microns and 2 pa ts of abieti acid chloride, respectively.

Example I V Example I was repeated with the exception that 41.5 par s of coconut oi fa y ac d chloride and .2 p t of ground sodium isethionate were replaced by 1 part of ground Z-hydroxy-butane sodium sulfonate having a particle size of 3 microns and v1.3 parts of a commercial mixre of n pht nie a h o d p pa ed i em a comme i y a l ble pht eni id mix ure ha ing an apparent molecular weight of 200.

Example V Example I was again repeated with the exception that the core actants were replaced by 2 parts of dodecyl z i ac h r nd l pa 'of g und Z-hydmxY- propane sodium sulfonate having a pa ticle size of 7 amounted to approximately 85%.

esters of carboxylic acids which comprises grinding, to

a particle size ranging between 3 and microns, a salt of a 2-hydroxyalkane sulfonic acid selected from the class consisting of those of the following formulae:

wherein R represents a member selected from the class consisting of hydrogen and lower alkyl, M represents a salt-forming group selected from the class consisting of alkali metals, alkaline earth metals, metals of periodic table group 2B, tn'ethanolamine, quinoline and pyridine, and m represents an integer of from 1 to 2, intimately mixing the said ground salt with a carboxylic acid chloride of at least 6 carbon atoms selected from the group consisting of aliphatic and alicyclic carboxylic acid chlorides devoid of reactive interfering substituents to form a homogeneous non-settling slurry, continuously feeding said slurry to a metallic surface heated to approximately -170 C., and recovering the said ,G-snlfoalkylester as a broken film which is friable on grinding.

2. The process according to claim 1 wherein the carboxylic acid chloride .is coconut acid chloride.

3. The process according to claim 1 wherein the car boxylic acid chloride is oleic acid chloride.

4. The process according to claim 1 wherein the earboxylic acid chloride is abietic acid chloride.

5. The process according to claim 1 wherein the carboxylic acid chloride is naphthenic acid chloride.

6. The process according to claim 1 wherein the carboxylic acid chloride is dodecylbenzoic acid chloride.

References Cited in the file of this patent UNITED STATES PATENTS 1,881,172 Daimler et al. Oct. 4, 1932 1,916,776 Steindorfi et al. July 4, 1933 2,236,541 Katzman Apr. 1, 1941 2,293,265 Mikeska Aug. 18, 1942 OTHER REFERENCES Hoyt: German Chemical Developments in Synthetic Detergents and Wetting Agents, PB-3868, 1945, pp. 20 and 30. 

1. A CONTINUOUS PROCESS FOR PREPARING B-SULFOALKYLESTERS OF CARBOXYLIC ACIDS WHICH COMPRISES GRIDING, TO A PARTICLE SIZE RANGING BETWEEN 3 AND 10 MICRONS, A SALT OF 